The Attic Renovation

Finishing the second floor of a 1 1/2 storey house.

Some problems were more obvious than others.  For example, there was some water staining on the trim around the back window in the large bedroom.  I chalked it up to poor installation and caulking of the window and assumed that the problem was solved when I had the window replaced.  Unfortunately, when I removed the trim to inspect the damage closer, I realized that it would take more than some drywall compound to fix this spot.

The most serious problem with the second floor was that the insulation was attached directly against the roof deck rather than allowing an air space for ventilation.  We learned of this issue when I removed a section of drywall to allow the air handler installers access to the side attic to run ductwork.  This led me to completely gut the second floor, removing all the drywall, insulation and wiring.

The insulation was mineral wool with kraft paper facing on both sides.  In the climate of my area, code requires an airspace between the roof deck and insulation in a cathedral ceiling such as this.  In the summer, this allows for the movement of air to keep the roof cooler, thus preventing the premature deterioration of the shingles.  In the winter, this air space keeps the heated indoor air from melting snow on the roof, which can lead to ice dams in below-freezing temperatures.  You can see what effect improper installation can have on insulation.  It was impossible to remove the batts in one piece as they disintegrated to the touch.

The insulation and drywall were installed right up to the roof peak.  In the picture to the right, you can see the plumbing for the solar panels which were removed when the roof was re-shingled. 

Once the drywall was removed in the guest room, some obvious repair work was exposed.  Apparently about 20 years ago, there had been a fire in this room.  New fiberglass insulation had been installed, but unfortunately it was installed in the same manner as the old insulation.  The vapour barrier was only 4 mil rather than 6 and was about as useful as Saran Wrap.  You  can see significant moisture damage on the fiberglass batts.

With the walls opened up, another issue became evident.  The house had been wired with low voltage remote switches, which is not a necessarily a problem.  The advantage is that a light or other fixture can be controlled by switches in several locations.  The low voltage wiring works well for retro-fit situations as the 18 pr 16 gauge wire is easy to run, does not require conduit, and the switches, depending on the local code, do not have to be mounted in boxes.  The voltage to the wires is only 24 volts, virtually eliminating any shock hazard.

However, the system is a bit more complicated than traditional wiring, consisting of a transformer and relays.  Plus whoever wired this house had gone overboard.  The large bedroom had 9 fixtures-- combination of lights and plugs-- that were operated in various combinations by 7 switches in 4 locations in a 10x14 room.  Overkill does not begin to describe this configuration.  For example, one switch would operate a plug and an overhead light.  Another switch would operate two other plugs and another light.  Another switch would operate the first light and a fourth plug.....you get the idea.

Tracing the wires would be very difficult, if not impossible, given the mess of spaghetti at the relays and switches.  The picture to the right is an example of one of these junctions.  To add further complications, this particular junction was above the ceiling, completely inaccessible.

The transformer was located in the basement, in an area that was very difficult to access.  I determined which circuit was supplying power to the switches and set about tracing each wire from the second floor down to the basement and disconnecting it at the transformer.

In general, the wiring in this house was a mess.  Removing as much spaghetti as possible makes tracing other circuits easier.  The picture on the right is typical of how much of the house was wired.  Removing the low voltage wiring was one of the first steps in de-cluttering the house's electrical system.